Water cooler



FIG. 1 is a front perspective view of a water cooler showing our new design;

FIG. 2 is a rear elevational view of the water cooler shown if FIG. 1;

FIG. 3 is a front elevational view of the water cooler;

FIG. 4 is a left side elevational view thereof,

FIG. 5 is a right side elevational view thereof; and,

FIG. 6 is a top plan view of the water cooler. 

The ornamental design for a water cooler, as shown and described. 